Levantamento molecular dos casos positivos de dengue na macrorregional de saúde de Juiz de Fora

Abstract

Arboviral diseases represent a significant global public health problem and are mainly transmitted by hematophagous arthropods, such as mosquitoes. Among these diseases, dengue stands out due to its high incidence and wide dissemination in tropical and subtropical regions, particularly in Brazil, where it presents intense viral circulation and recurrent epidemic outbreaks. In this context, laboratory diagnosis and molecular surveillance become essential tools for case confirmation, identification of viral serotypes, and monitoring of the circulation dynamics of the dengue virus (DENV). The present study aimed to analyze the positivity of molecular tests for dengue and the circulation of viral serotypes in the coverage area of the Regional Health Superintendence (SRS) of Juiz de Fora, Minas Gerais. This is a quantitative, observational, retrospective, and cross-sectional study based on the analysis of secondary data obtained from health information systems. The study population consisted of 6,006 patients attended within the Brazilian Unified Health System (SUS) across 37 municipalities covered by the Regional Health Superintendence of Juiz de Fora between December 2023 and June 2025. These patients presented clinical suspicion of dengue and were submitted to laboratory investigation using RT-qPCR. Between December 2023 and June 2024, a predominance of the DENV-1 serotype was observed, with increased positivity between February and April, highlighting the seasonal pattern of the disease. In the subsequent period, from December 2024 to June 2025, a shift in viral circulation occurred, with predominance of DENV-2 and sporadic reintroduction of DENV-3. The spatial distribution demonstrated a strong concentration of cases in the municipality of Juiz de Fora, reflecting its role as a regional center for healthcare services and diagnostic testing. A higher frequency of cases was observed among adolescents and young adults, while the distribution between sexes was similar. The data confirm the seasonal behavior of dengue, with peaks associated with the rainy season. Overall, the results demonstrate viral cocirculation, spatial heterogeneity, and epidemiological dynamics consistent with patterns observed in other regions of Brazil, reinforcing the importance of continuous molecular surveillance and the strengthening of disease control and monitoring actions.